Rhinoceros Auklet

Cerorhinca monocerata

By Andrew McCormick

Length 15" long

Wingspan 22"

Weight 1.1 lb

AOU Band code RHAU

The Rhinoceros Auklet is named for the horn at the base of its bill. It is in the genus cerorhinca (horn-nose) from the Greek keras, horn, and rugkhos, snout. Rhinoceros is made up of the same two Greek elements which are reversed. Auklet, a little auk, is derived from the Old Norse alka, which refers to a number of northern birds (Holloway).

With its dark gray head and dark back and chest the Rhino can be difficult to see on the water. Fortunately, its angular head and heavy, yellow-orange bill provide a distinctive silhouette. Its belly and undertail coverts are a dull white. In breeding season the horn is whitish and prominent at the base of the bill but it sheds by fall. Also impressive during breeding are the two sets of white facial plumes. These however fade in winter. Most of the Rhinos in Washington waters winter at sea but individual birds can often be seen in Puget Sound. The birds make mooing and coughing sounds on the breeding grounds, but at other times of year are fairly silent.

In March and April, Rhinos head to their island nesting colonies primarily along the coast of British Columbia and Southeast Alaska. Smaller numbers nest on the Farallon Islands off California and on Protection Island, WA. The birds construct a shallow nest lined with moss and twigs in a side chamber of a burrow which they have dug 5-10 feet into a grassy or wooded hillside. A single egg is incubated by both parents for 40-50 days and the young bird leaves the nest in another two months. Rhinos are the only auklets that are nocturnal feeders. Scientists think this is a new behavior in response to kleptoparasitism by gulls and attacks by Bald Eagles which hunt for auklets on the breeding sites (Gaston and Dechesne). The bird has a distinctive but poorly studied mechanism for herding fish such as sand lance and herring by emitting bubble trails which seem to prevent the schools from breaking up. They are able to capture fish while holding others in their bill and are able to return a “bill load” of one to several fish back to the nest (Gaston and Dechesne).

Rhino populations are stable but can be at risk to local predators in the burrows because of their low birth rate. This is partially balanced by a greater opportunity to breed during their long life span which can reach 25 years (Sibley). Conservation efforts have been successful. Eradication of raccoons (British Columbia), foxes (Alaska) and rabbits (California) has allowed Rhinos to reestablish their colonies. In 1968 sheep were removed from Protection Island and the number of burrows rose from 3,500 to 28,000 by 1974 (Gaston and Dechesne). The Rhinoceros Auklet is a small bird on a big ocean, so look for them on Puget Sound.

Photo by Mick Thompson

Double-crested Cormorant

Phalacrocorax auritus

By Hugh Jennings

Length 32 in

Wingspan 52 in

AOU Band code DCCO

The Double-crested Cormorant (DCCO) is about 32" long and has a wing span of about 52". Its genus phalakros is from Greek for bald, and kora for crow or raven. The family includes only cormorants of which there are 30 in the world and 6 in North America. The species auritus is Latin for eared or crested and refers to the rarely seen tufts on the crown.

It is the only cormorant likely to be seen inland. Both sexes are essentially alike: large, black, with a long tail. They have a yellow-orange throat patch year-round. First-year birds are brown above, pale below, but usually palest on upper breast and neck. The DCCO is distinguished from Brandt’s Cormorants by more buoyant flight and flying with a kinked neck. They can be seen soaring high, using air currents to gain altitude and then coasting on a long glide. They may have trouble taking off from land and water. They often need to run along the water to gain speed.

The DCCO is found along either coast and on inland rivers and lakes wherever fish are plentiful. The birds feed by diving and swimming underwater, eating mostly fish. They may hold their wings out to dry after diving in the water. They nest on rocky islands, cliffs facing water, or stands of trees near water. The cormorants seen on freshwater lakes in our area are usually seen only from about October to April. During the spring and summer they are at nesting areas.

The DCCO nest in colonies. The nest is a platform of sticks and seaweed lined with leafy twigs and grass, and placed in a tree or on the ground. There are 2-7 pale blue eggs. Incubation is 24-29 days and the young fledge 35-42 days after hatching. The birds are silent away from the nest, but at the nest they can give a variety of deep croaks and grunts.

Photo by Mick Thompson

Pigeon Guillemot

Cepphus columba

By Hugh Jennings

Length 13.5 in

AOU Band code PIGU

The Pigeon Guillemot (PIGU) is a member of the auk family and is about 13-1/2” long. It is generally found close to rocky shores along the Pacific Coast from Alaska to California. The genus name Cepphus is from the Greek kepphus meaning sea bird; the species name columba is from the Latin for dove or pigeon.

The breeding adult is all black except for a white wing patch and red feet(both sexes look alike). It has a pointed black bill. It resembles the Black Guillemot which is found on the Atlantic and Arctic coast, except that a wedge-shaped bar of black extends into the prominent white wing patch. The winter plumage is mostly white; upper parts are mottled dark brown with white below, and wings are blackish with a white patch.

Both guillemots have a "water dance" in the spring in which pairs sometimes gather on the water near the nesting colony for a mutual display, calling and showing off the red linings of the mouth. They will form lines on the water for a few seconds which suddenly break up when the whole party dives with individuals chasing each other below the surface, while floating on the surface.

Its diet consists of small fish and marine life, such as shrimp, crab, worms, mollusks and small octopus. It forages by swimming underwater propelled mainly by its wings. It uses its feet mostly for steering, but also for some propulsion. It feeds mostly within 50 ft. of the surface, but can dive to 150 ft.

Pairs nest alone or in small colonies of up to 50 pairs. The nest site is in crevices, in caves or in talus slopes at the foot of cliffs on rocky islands near salt water. It even uses abandoned burrows of puffins, under railroad ties and in burrows in clay banks in the Puget Sound region of Washington, where it digs its own burrows, sometimes in banks 200 ft. above the sea. The same nest site may be used for many years. The nest is a shallow scrape in a pile of dirt, pebbles, or shells. There are only 1 or 2 eggs, creamy to pale blue-green with gray and brown blotches concentrated near the large end. Incubation is by both sexes for 26-32 days.

Both parents fed the young, bringing them small fish. The young leave the nest 29-54 days after hatching, usually at night, scrambling or fluttering down to the water. They are able to swim and dive immediately, but are not capable of strong flight for another 2-3 weeks.